Spain approved AstraZeneca's coronavirus vaccine for use in people aged 18 to 55 on Friday, becoming the latest country to limit the shot to younger people due to a lack of data on its use among the elderly.
Italy also recommends its preferential use for adults of 55 and under, while Germany, France, Austria and Norway will only administer the shot to people younger than 65.
Separately, Madrid confirmed on Friday the region's first case of the Brazilian COVID-19 variant, while the national health ministry said it was not aware of any other cases of the highly contagious strain on Spanish territory.
Catalan authorities announced Spain's second known case of the South African variant on Wednesday, a day after the government restricted air travel with Brazil and South Africa to curb the spread of the virulent new strains from those countries.
A third wave of COVID-19 infections has been slowing, with Spain's 14-day incidence rate falling to 751 cases per 100,000 people on Friday from 900 cases in late January, but officials say the arrival of the new strains could drive a resurgence.
The health ministry recorded 28,565 new cases on Friday, bringing the total above 2.94 million, while the death toll climbed by 584 to 61,386.
"IT'S VERY CONFUSING"
In an initial phase aimed at protecting care-home residents and workers and front-line medics, Spain has administered 1.87 million doses produced by Pfizer and Moderna.
It expects a delivery of 1.8 million AstraZeneca doses in February to speed up the pace of inoculation and help it hit a target of vaccinating 70% of the population by summer.
Nearly three quarters of Spaniards are willing to receive a shot as soon as one became available, according to a poll by the Centre for Sociological Studies (CIS) but some remain wary.
"At the moment I will not get one. I will wait a bit," said 80-year old retired lawyer Livigno, out walking in central Madrid. "You hear positive and negative comments and it's very confusing. I am not even sure the government is clear."
In one rare bit of good news from the COVID frontline, two patients recovering from the virus, Fernando, 70, and Rosario, 62, got married at Madrid's Hospital Isabel Zendal after he proposed to her via WhatsApp. They were married by a priest via videolink.